Filling machine for open mouth bags



April 22, 1958 c. F. CARTER 2,831,510

FILLING MACHINE FOR OPEN MOUTH BAGS Filed Feb. 28, 1955 /4 I 32 f 3 [3/ 30) K?) 37 VACUUM VACUUM INVENT OR Clarence) Larkr "M @M? 42m ATTORNEYS 2,831,510 FHJLING MACHlNF: FGR OPEN MOUTH BAGS Clarence F. Carter, Danville, Ill.-

Application February 28, 1955, Serial No. 490,941

3 Claims. (Cl. 14159) This invention relates generally to a machine for filling air pervious wall bags of the open mouth type. More specifically, the invention relates to an apparatus for filling open mouth bags with finely divided powdered material wherein the creation of a vacuum or low pressure within the bag interior is effective to fill the bag.

In several of my prior patents, directed to the filling of receptacles with particulate materials, the use of a vacuum or low pressure has been employed to assist in drawing the particulate material into the receptacle and/ or to withdraw air from the receptacle as the particulate material is dispensed thereinto. The use of a low pressure in connection with filling operations has been found to produce rapid filling and also give improved compacted filling of the receptacles.

In the filling apparatus of the instant invention, as described in detail hereinafter, the filling of open mouth bags made of an air pervious material is performed. Such bags are conventionally made of paper, such as lrraft paper, which is pervious to air to the extent that when subjected to a vacuum on one side of a wall thereof, air will be drawn through the bag wall.

it is an object of this invention to provide an improved bag filling machine constructed to facilitate the introduction of the bag into its position for filling and wherein the filling of the bag is promoted by drawing a vacuum in the bag interior through the interstices of the bag wall.

It is a further object of this invention to provide a bag filling machine employing side plate means disposed on opposite sides of the bag to be filled and positioned beneath a filling spout with means for applying vacuum to the bag walls by utilization of the side plate means and further having a seal adjacent the spout to preclude the entrance of air into the bag interior around the mouth of the bag being filled.

It is also an object of this invention to provide a bag filling machine having a vertically movable supporting base for lifting the bag into filling position, side plates horizontally movable away from one another to apply vacuum to the bag walls and a filling spout disposed above the base and provided with a seal to engage with the mouth of the bag being filled.

Additional purposes and objects of the invention will become apparent from the description of a specific embodiment thereof as shown on the accompanying drawing which forms a part of this application. The single figure on the drawing is a sectional view of the filling machine of the instant invention showing an open mouth bag positioned for the filling operation.

As shown on the drawing, a bag lifting base 16 carried on the rod 11 of a pneumatic extensible actuator 12 is positioned directly below the open end of a filling spout 13. it will be appreciated that suitable pipe connections are provided for the actuator 12 by means of which the raising and lowering of the base may be controlled by regulation of the admission of pressurized fluid to actuator 12. The filling spout 13 connects at its upper end with a suitable supply hopper (not shown) and pref- 2,831,510 Patented Apr. 22, 1958 erably will have a material control valve (not shown) interposed between the filling spout and the outlet of the supply hopper.

An expansible seal 14 is provided surrounding the lower end of filling spout 13. This seal, preferably formed of a resilient rubber material, may be expanded upon the application of pressurized fluid to the interior thereof to clamp the mouth of the bag to be filled onto the filling spout and preclude air from entering the bag through its month during the filling operation. As shown on the drawing, a seal support 15 is mounted exteriorly of the seal 14. Support 15"serves to back up the seal in its expanded condition so that the mouth of the bag being filled will be urged into firm continuous engagement with the support by expansion of seal 14, thereby resulting in clamping the bag onto filling spout 13. On the drawing a bag B to be filled is shown positioned with its mouth M engaged with the filling spout 13.

An adjustable limit stop 16 is provided on the filling spout 13 at a point above the location of seal 14. Stop 16 provides a downwardly facing annular shoulder which is engaged by the upper end of the mouth M of the bag. By appropriate vertical movement of stop 16 relative to spout 13, the upper limit or extent to which the bag mouth may slide onto the spout for filling may be varied.

A pair of side plates 20 and 21 are mounted in spaced relation beneath the filling spout 13. These plates have grooves 22 milled thereinto to promote the application of vacuum or reduced pressure to the maximum exterior surface of the bag which is covered by the plates. Conduit means 23 and 24 are provided to couple the opposed grooved surfaces of plates 20 and 21 to a source of vacuum with pressure-actuated diaphragm valves 25 and 26 disposed in the respective conduit means 23 and 24 to enable controlling of the application of vacuum to plates 20 and 21.

The plates 20 and 21 are supported on pairs of parallel shafts 30 and 31 respectively. Grooved guide rolls 32' are rotatably mounted on opposite sides of shafts 30 to engage with the shafts and thereby support them and plate 20 carried thereon. Similarly, grooved rolls 33 are rotatably mounted on opposite sides of shafts 31 to engage with shafts 30 to support them and plate 21 carried thereby. The rotatably mounted rolls, engaging with the pairs of shafts 30'and 31, permit horizontal movement of plates 20 and 21 away from bag B. To effect movement of plates 20 and 21 horizontally away from and toward one another, an extensible actuator 35 is provided with the actuating rod 36 thereof connected to plate 20 and a similar extensible actuator 37 provided with its actuating rod 38 connected to plate 21. As in the case of actuator 12, suitable pipe connections are provided to direct operating pressurized fluid into the respective actuators 35 and 37.

i It will be appreciated that on the drawing only the basic elements have beenillustrated. Thus, the various supporting members and parts incidental to the mounting of the illustrated elements have, for simplicity of illustration, not been shown. It will be readily recognized that from the disclosure set forth herein a person skilled in the art could eifect numerous changes and modifications in developing a specific structure to embody the features of the instant invention without departing from the scope of this invention.

Having described the structure of the open mouth bag filling machine of this invention, reference will now be had to a preferred mode of operation for the use of such structure. With the base 10 in its lowered position, an open mouth bag is placed on the base. At this point the side plates 20 and 21 are retracted by means of their respective actuators 35 and 37. Also, the expansible seal 14 is deflated to provide a space between such seal and support 15. Further, the valves 25 and 25 will be closed to cut ofi the source of vacuum to the opposed grooved surfaces of plates 20 and 21.

By appropriate admission of pressurized fluid to actuator 12, the base is raised to move the mouth M of the bag upwardly between the seal 14 and support 15. The upper end of the bag mouth engages stop 16 to limit the extent of movement of the mouth of the bag onto the filling spout. The side plates 20 and 21 are moved toward one another by the application of pressurized fluid to actuators 35 and 37. Pressurized fluid is admitted to expansible seal 14 to expand such seal outwardly so as to clamp the mouth of the bag against support 15. The bag is thus properly positioned for initiation of the filling operation.

Valves 25 and 26 are opened to apply vacuum or reduced pressure over the exterior of the bag and thus draw a vacuum within the bag interior through the porous walls of the bag. The material supply valve is thereupon opened and the powdered material dispensed into the bag. During dispensing of material into the bag, the air initially present within the bag is withdrawn therefrom and also air entrained between the powdered particles is drawn through the bag walls. The exodus of powder from the bag is precluded by the nature of the material used in the construction of the bag while seepage of air into the bag through the mouth thereof is prevented by reason of seal 14 clamping the bag onto the filling spout 13.

Upon filling of the bag to the desired level, the material supply is cut ed and the application of the vacuum to the side plates terminated. Then the side plates are moved away from the filled bag under the control of their respective actuators 35 and 37. The expansible seal 14 is deflated to release the mouth of the bag from the filling spout 13. Subsequently, the base 10 is lowered,

under control of actuator 12, to enable removal of the filled bag from the machine.

It will be appreciated that various modifications and variations may be made in the specific structure illustrated within the scope of the appended claims, As an example, referring to the structure of expansible seal 14 and support 15, it will be appreciated that, if desired, the expansible seal could be constructed to surround the exterior of the bag mouth M and force the mouth into engagement with the exterior of spout 13. With such a construction, support 15 would be unnecessary since, in efiect, the exterior surface of the spent 13 functions as a back-up support for the seal in its expanded condition.

Having thus described my invention, what I claim is:

1. A bag filling machine comprising a base to support the bag to be filled, a downwardly opening filling spout mounted above said base, a pair of side plates disposed in spaced relation and extending between said base and said spout to provide a cavity therebetween substantially completely enclosing the bag to be filled, support means for said plates to move said plates away from each other to facilitate positioning of the bag to be filled in cooperative engagement with the filling spout, means for applying a vacuum to the opposed inner surfaces of said plates to withdraw air from the bag interior during introduction of material into the bag, releasable seal means carried adjacent the filling spout cooperable with the mouth of the bag to be filled to preclude air from entering the mouth of the bag during filling, and support means for said base to effect raising of the bag to be filled into cooperative engagement with the filling spout and seal means.

2. A bag filling machine as recited in claim 1 wherein said support means includes extensible pneumatic actuators connected to said base and to each of said side plates to efiect movement of said base and said side plates away from said filling spout to facilitate introduction of the bag to be filled into the filling cavity.

3. A bag filling machine as recited in claim 1 further having a stop adjustably carried by said filling spout above said seal means and adjustable vertically on said spout to limit the upward movement of the bag mouth past said seal means onto said filling spout.

References Cited in the file of this patent UNITED STATES PATENTS 1,782,733 Lilly Nov. 25, 1930 2,178,494 Richardson Oct. 31, 1939 2,281,516 Royal Apr. 28, 1942 2,283,093 Rosenthal et al. May 12, 1924 2,513,143 Carter June 27, 1950 FOREIGN PATENTS 48,984 Austria Apr. 10, 1910 465,086 Germany Sept. 6, 1928 

